Elastomers are useful as elastic nonwovens or films in applications ranging from waistbands, side panels, closure systems, and chasses for baby diapers, adult incontinence and personal hygiene garments, as well as other applications. Most of these elastic closures are constructed with facing layers that include a nonwoven substrate that is plastic in properties and provides aesthetic attributes such as touch and feel. Examples of such include those disclosed in U.S. Patent Publication No. 2008/0045917 and its counterparts. The plastic facing layers sandwich the elastic (core) layer, which is inherently elastomeric and possesses a rubbery feel that is not desirable for skin contact.
More recently, highly elastic, breathable, nonwoven fabric with the necessary aesthetic qualities that require no form of mechanical activation have been desired. Existing products are complex laminates of an elastic film, and are typically a styrenic block copolymer (“SBC”) or polyurethane as the elastic film that can have polyolefin skins coextruded onto the film to prevent blocking, and nonwovens in order to provide the correct aesthetic (a soft, fluffy, cushion-like texture) and in certain constructions a hot melt glue layer to bond the nonwoven to either side of the elastic film. These types of constructions, once formed, are often not elastic due to the constraining influence of the inelastic components such as the polyolefin skin layers, adhesive, and nonwoven facing layers.
In order to remove the constraining influence of non-elastic elements, many composites require a mechanical stretching or activation process in order to stretch or break the non-elastic components. The mechanical stretching removes the constraints and creates an elastic composite controlled by the SBC film. Furthermore, such composites require the film to be apertured or perforated to make these laminates breathable. This process involves the controlled puncturing/tearing of the film with the associated concerns for film failure and increased scrap rates.
Work in this area has been discussed in U.S. Pat. Nos. 5,272,003; 5,366,782; 6,075,179; 6,342,565; 7,026,404; U.S. Patent Publication Nos. 2008/0199673; 2008/0182116; 2008/0182940; 2008/0182468; 2006/0172647; 2005/0130544; 2005/0106978; and PCT International Publication No. WO 2008/094337. There is still a need, however, for new fabrics and methods for making the same that can provide different performance attributes in a single fabric without activation processes being essential for product performance.